Quadrilobe connector for transmitting torque

ABSTRACT

A quadrilobe connector defined by a cross-sectional shape derived from a square, where each of the corners of the square is replaced with an arc of a circle, and ends of two adjacent arcs meet to form a depression between the arcs. Further, each of the four arcs is equal in radius and intersects tangentially to each other arc.

BACKGROUND OF THE DISCLOSED TECHNOLOGY

As known in the art, torque generated by various tools, such as a socket wrench tool, is transferred to an end effector by a feature that has a square cross section, such as a connector having a square cross section. However, transferring torque through the square feature creates high stress in the corners of the square, which are weak points in the design of such devices. Further, manufacturing the male and, more so, the female part of the square feature requires specialized machinery.

The square drive with a spring loaded pin or ball to retain the end effector, as used in the prior art, is only reliably usable with light weight effectors such as small sockets. While, the square drive feature with a retainer pin and elastomeric ring can hold heavy end effectors, those effectors have loose parts which are easily lost and require many steps to install.

There is thus a need in the art for a connector or fastener for use in a tool such as a socket wrench tool, having a non-square cross section which may receive the torque generated by the tool without putting high stress on the connector.

U.S. Pat. No. 7,225,710 to Pacheco, Jr. discloses a lobed fastener with six lobes. The lobes are curvilinear having depressions which are joined from two arcs extending from corners of a hexagonal structure. The length of each lobe and each depression is unequal.

U.S. Pat. No. 8,347,761 to Goss discloses a socket with six rounded lobes, wherein the corners of a hexagon are replaced with an arc of a circle. The ends of two adjacent arcs do not seem to meet to form a depression between the arcs.

U.S. Patent Publication 2012/0165107 to Guo et al. discloses a plurality of engaging teeth formed on an inner peripheral wall of an engaging hole. In one embodiment, six rounded lobes are spaced there-around a male connector. The female connector has rounded lobes. In this reference the corners of a hexagon are replaced with an arc of a circle and ends of two adjacent arcs do not seem to meet to form a depression between the arcs.

SUMMARY OF THE DISCLOSED TECHNOLOGY

The disclosed technology described herein addresses a need, unfulfilled in the prior art, for providing a connector for a torque generating device which is not rapidly worn or sheared by stress resulting from the generated torque being transferred through the connector, and a torque generating device using such a connector.

In accordance with one aspect of an embodiment of the disclosed technology, there is provided a quadrilobe connector including a male connector portion including a quadrilobe shaped protrusion and a female connector portion including a quadrilobe shaped socket, corresponding in shape to the quadrilobe shaped protrusion and configured to receive the quadrilobe shaped protrusion for connection thereof, wherein the quadrilobe shape is defined by a cross-sectional shape derived from a square, such that each corner of the square is replaced with an arc of a circle, the arc defining a lobe of the quadrilobe shape, ends of each two adjacent the arcs meet to form a depression between the adjacent arcs, and each of the arcs is equal in radius and intersects tangentially to each other the arc.

In some embodiments, a radius of each the lobe and of each the depression is equal.

In some embodiments, each arc is defined by a circle having a first radius, and each depression is defined by an arc of a circle having a second radius. In some such embodiments, the first radius is equal to the second radius.

In some embodiments, the male connector portion is mounted on an output shaft of a torque generating device, and forms a drive connector for the device. In some such embodiments, the female connector portion comprises a socket disposed in a replaceable piece removably and replaceably connectable to the torque generating device.

In some embodiments, the female connector portion comprises a socked disposed within an output shaft of a torque generating device, and forms a drive connector for the device. In some such embodiments, the male connector portion protrudes out of a replaceable piece removably and replaceably connectable to the torque generating device.

In some embodiments, engagement of the quadrilobe protrusion of the male connector portion in the quadrilobe socket of the female connector portion during activation of a torque generating device results in distribution of the torque generated by the device on wall portions defined by the arcs and the depressions, thereby reducing stress caused by the generated torque on the torque generating device.

In accordance with one aspect of an embodiment of the disclosed technology, there is provided a torque generating device, including a body portion adapted to be held by a user during operation of the device and a quadrilobe connector mounted on the body portion, the quadrilobe connector having a geometrical shape defined by a cross-sectional shape derived from a square, such that each corner of the square is replaced with an arc of a circle, the arc defining a lobe of the quadrilobe shape, ends of each two adjacent the arcs meet to form a depression between the adjacent arcs, and each of the arcs is equal in radius and intersects tangentially to each other the arc.

In some embodiments, the quadrilobe connector comprises a male quadrilobe connector portion mounted on and protruding from an output shaft functionally associated with the body portion. In some such embodiments, the device further includes a replaceable piece removably and replaceably connectable to the torque generating device via the quadrilobe connector, the replaceable piece comprising a female quadrilobe connector portion forming a socket disposed therein, the socket corresponding in shape to the quadrilobe protrusion of the male quadrilobe connector portion and configured to receive the male quadrilobe connector portion for connection of the replaceable piece to the body portion.

In some embodiments, the quadrilobe connector comprises a female quadrilobe connector socket portion disposed within an output shaft functionally associated with the body portion. In some such embodiments, the device further includes a replaceable piece removably and replaceably connectable to the torque generating device via the quadrilobe connector, the replaceable piece comprising a male quadrilobe connector portion protruding therefrom, the protrusion corresponding in shape to the quadrilobe socket of the female quadrilobe connector portion and configured to be received therein for connection of the replaceable piece to the body portion.

In some embodiments, the torque generating device comprises a hydraulic torque wrench or a pneumatic torque wrench or an electric torque wrench.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a square male drive connector and a corresponding square female socket connector of the prior art.

FIG. 2 shows a perspective view of a square male drive connector forming part of a torque generating device and a corresponding square female socket connector of the prior art.

FIG. 3 shows a perspective view of a quadrilobe male drive connector and a corresponding quadrilobe female socket connector of embodiments of the disclosed technology.

FIG. 4 shows front plan view and side elevation view of the quadrilobe male drive connector of FIG. 3.

FIG. 5 shows a perspective view of a quadrilobe male drive connector forming part of a torque generating device and a corresponding quadrilobe female socket connector of embodiments of the disclosed technology.

FIG. 6 shows a perspective view of a quadrilobe female drive connector and a corresponding quadrilobe male connector of embodiments of the disclosed technology.

FIG. 7 shows a perspective view of a quadrilobe female drive connector forming part of a torque generating device and a corresponding quadrilobe male connector of embodiments of the disclosed technology.

FIGS. 8A to 8E are schematic illustrations of geometrical progression of generating a quadrilobe shape as used in the disclosed technology.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE DISCLOSED TECHNOLOGY

The presently disclosed technology is directed towards a quadrilobe socket connector designed to lower the stress level on the walls of male and female connecting socket devices when they are engaged. The quadrilobe shape allows the socket to transfer more torque, be more durable, and be procured less expensively than the prior art versions as standardized machinery may be used in the manufacture of same.

FIG. 1 shows a perspective view of a square male drive connector of the prior art, and of a corresponding female socket connector of the prior art. As seen, the body 100 of a torque generating device comprises an output shaft 102, having protruding therefrom a square male drive connector 104. An attachment 106 designed to connect to the torque generating device, includes a square female socket connector 108 corresponding in shape to drive connector 104 and designed to receive drive connector 104 for connection therewith.

FIG. 2 shows a perspective view of a square male drive connector of the prior art forming part of a torque generating device, and a corresponding square female socket connector of the prior art. As seen, a torque generating device 110, here illustrated as a torque wrench, includes a body 100 including an output shaft 102 and a square male drive connector 104, as shown in FIG. 1, as well as additional typical portions such as a grip 112, an activation button 114, and the like. An attachment 106 as shown in FIG. 1, includes square female socket connector 108 corresponding in shape to drive connector 104 and designed to receive the drive connector 104 for connection therewith. For example, attachment 106 may form part of a larger tool (not shown).

During use of the torque generating device 110, for example by activation of activation button 114, the torque generated by the device transfers through the square male drive connector 104, causing high stress levels on the corners of the square shape male drive connector 104 and of the corresponding square female socket connector 108 and leading to excessive wear and premature failure of the device 110.

FIG. 3 shows a perspective view of a quadrilobe male drive connector and a corresponding quadrilobe female socket connector of embodiments of the disclosed technology. FIG. 4 shows front plan view and side elevation view of the quadrilobe male drive connector of FIG. 3.

As seen in FIGS. 3 and 4, a body 200 of a torque generating device comprises an output shaft 202, having protruding therefrom a quadrilobe male drive connector 204. An attachment 206 designed to connect to the torque generating device, includes a quadrilobe female socket connector 208 corresponding in shape to drive connector 204 and designed to receive drive connector 204 for connection therewith. When connected, a front end 205 of male drive connector 204 contacts an inner surface of the female socket connector 208.

The quadrilobe shape of drive connector 204 and of corresponding socket connector 208 is defined as having a cross-sectional shape derived from a square, whereby each of the corners of the square is replaced with an arc 210 of a circle, whereby ends of two adjacent arcs meet to form a depression 212 between the arcs. In some embodiments, each of the four arcs 210 is equal in radius and intersects tangentially to each other arc 210. In some embodiments, the radius of each lobe, and each depression 212, is equal.

In another embodiment, a square connector with rounded corners may be used. In yet another embodiment, more than four lobes may be used, such as five or six lobes.

Turning specifically to FIG. 4, the front plan view shows the four depressions 212 between the arcs on the front end 205 of the male drive connector 204. Furthermore, the side elevation view shows a view of a depression 212 between the arcs 210 of the male drive connector 204, from the side.

FIG. 5 shows a quadrilobe male drive connector of embodiments of the disclosed technology forming part of a torque generating device and a corresponding quadrilobe female socket connector of embodiments of the disclosed technology. As seen, a torque generating device 220, here illustrated as a torque wrench, includes a body 200 including an output shaft 202 and a quadrilobe male drive connector 204, as shown in FIG. 3, as well as additional typical portions such as a grip 222, an activation button 224, and the like. An attachment 206 as shown in FIG. 3, includes quadrilobe female socket connector 208 corresponding in shape to drive connector 204 and designed to receive the drive connector 204 for connection therewith.

It is a particular feature of the teachings herein that the quadrilobe shape of the male drive connector 204 and the female socket connector 208 has rounded edges, made of four connected arcs 210. This shape avoids sharp corners where high levels of stress are caused in prior art connectors, and allows for greater forces between the male and female connectors as compared to the prior art. As a result, the quadrilobe shape minimizes stress levels and extends the life of the socket connector. During use of the torque generating device 220, for example by activation of activation button 224, torque generated thereby is distributed by the new quadrilobe shape over a greater area of the socket connector leading to less pressure on the walls of the device than the square connector of the prior art.

FIG. 6 shows a perspective view of a quadrilobe female drive connector and a corresponding quadrilobe male connector of embodiments of the disclosed technology.

As seen in FIG. 6, a body 300 of a torque generating device comprises an output shaft 302, having disposed therein a quadrilobe female drive connector 304. An attachment 306 designed to connect to the torque generating device, includes a quadrilobe male connector 308, corresponding in shape to female drive connector 304 and designed to be received in drive connector 304 for connection therewith. When connected, an inner surface of female drive connector 304 contacts an end 309 of the male connector 308. The quadrilobe shape of female drive connector 304 and of corresponding male connector 308 is defined as described hereinabove with reference to FIG. 3, and include four arcs 310 whereby ends of two adjacent arcs meet to form a depression 312 between the arcs.

FIG. 7 shows a perspective view of a quadrilobe female drive connector of embodiments of the disclosed technology forming part of a torque generating device and a corresponding quadrilobe male connector of embodiments of the disclosed technology. As seen, a torque generating device 320, here illustrated as a torque wrench, includes a body 300 including an output shaft 302 and a quadrilobe female drive connector 304, as shown in FIG. 6, as well as additional typical portions such as a grip 322, an activation button 324, and the like. An attachment 306 as shown in FIG. 6, includes quadrilobe male connector 308 corresponding in shape to drive connector 304 and designed to be received in the drive connector 304 for connection therewith.

It is appreciated that though the disclosure herein relates to a specific type of torque generating tool, namely a pneumatic socket wrench, a quadrilobe connector as described herein may be used in any other suitable torque generating tool, such as, for example, a hydraulic or electric wrench.

FIGS. 8A to 8E are schematic illustrations of one method for geometrically generating a quadrilobe shape as used in the disclosed technology, using four circles.

As seen in FIG. 8A, a first step in development of a quadrilobe shape as used in FIGS. 3 to 7, is defining a circle 400 of diameter D, having a line 402 of length D, equal to the diameter of the circle, extending from the center 404 of the circle at a 45 degree angle. At the next step, illustrated in FIG. 8B, a second circle 406 having a diameter D is placed adjacent circle 400, such that the end of line 402 extending out of circle 400 engages the center 408 of circle 406.

In FIG. 8C, the geometrical construct of FIG. 8B is mirrored and centered over the geometrical construct of FIG. 8B such that the middle of line 402 (of FIG. 8B) intersects the middle of line 410 (of the mirrored geometrical construct), resulting in a flower-like geometrical construct 412. As seen, geometrical construct 412 includes a plurality of internal arcs 414, which are removed in FIG. 8D.

In FIG. 8E, four arcs are placed tangentially to arcs of the circles defining geometrical construct 412, so as to eliminate the sharp corners of geometrical construct 412, resulting a quadrilobe shape 420 as used in FIGS. 3 to 7. In some embodiments, the four arcs used to eliminate sharp corners are arcs of a circle having a diameter D, equal to the diameter D of the four circles used to define construct 412.

While the disclosed technology has been taught with specific reference to the above embodiments, a person having ordinary skill in the art will recognize that changes can be made in form and detail without departing from the spirit and the scope of the disclosed technology. The described embodiments are to be considered in all respects only as illustrative and not restrictive. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. Combinations of any of the methods, systems, and devices described herein above are also contemplated and within the scope of the invention. 

I claim:
 1. A quadrilobe connector comprising: a male connector portion including a quadrilobe shaped protrusion; and a female connector portion including a quadrilobe shaped socket, corresponding in shape to said quadrilobe shaped protrusion and configured to receive said quadrilobe shaped protrusion for connection thereof, wherein said quadrilobe shape is defined by a cross-sectional shape derived from a square, such that: each corner of said square is replaced with an arc of a circle, said arc defining a lobe of said quadrilobe shape; ends of each two adjacent said arcs meet to form a depression between said adjacent arcs; and each of said arcs is equal in radius and intersects tangentially to each other said arc.
 2. The quadrilobe connector of claim 1, wherein a radius of each said lobe and of each said depression is equal.
 3. The quadrilobe connector of claim 1, wherein each said arc is defined by a circle having a first radius, and each said depression is defined by an arc of a circle having a second radius.
 4. The quadrilobe connector of claim 3, wherein said first radius is equal to said second radius.
 5. The quadrilobe connector of claim 1, wherein said male connector portion is mounted on an output shaft of a torque generating device, and forms a drive connector for said device.
 6. The quadrilobe connector of claim 5, wherein said female connector portion comprises a socket disposed in a replaceable piece removably and replaceably connectable to said torque generating device.
 7. The quadrilobe connector of claim 1, wherein said female connector portion comprises a socked disposed within an output shaft of a torque generating device, and forms a drive connector for said device.
 8. The quadrilobe connector of claim 7, wherein said male connector portion protrudes out of a replaceable piece removably and replaceably connectable to said torque generating device.
 9. The quadrilobe connector of claim 1, wherein engagement of said quadrilobe protrusion of said male connector portion in said quadrilobe socket of said female connector portion during activation of a torque generating device results in distribution of the torque generated by the device on wall portions defined by said arcs and said depressions, thereby reducing stress caused by the generated torque on the torque generating device.
 10. A torque generating device, comprising: a body portion adapted to be held by a user during operation of said device; and a quadrilobe connector mounted on said body portion, said quadrilobe connector having a geometrical shape defined by a cross-sectional shape derived from a square, such that each corner of said square is replaced with an arc of a circle, said arc defining a lobe of said quadrilobe shape, ends of each two adjacent said arcs meet to form a depression between said adjacent arcs, and each of said arcs is equal in radius and intersects tangentially to each other said arc.
 11. The torque generating device of claim 10, wherein a radius of each said lobe and of each said depression of said quadrilobe connector is equal.
 12. The torque generating device of claim 10, wherein said quadrilobe connector comprises a male quadrilobe connector portion mounted on and protruding from an output shaft functionally associated with said body portion.
 13. The torque generating device of claim 12, also including a replaceable piece removably and replaceably connectable to said torque generating device via said quadrilobe connector, said replaceable piece comprising a female quadrilobe connector portion forming a socket disposed therein, said socket corresponding in shape to said quadrilobe protrusion of said male quadrilobe connector portion and configured to receive said male quadrilobe connector portion for connection of said replaceable piece to said body portion.
 14. The torque generating device of claim 10, wherein said quadrilobe connector comprises a female quadrilobe connector socket portion disposed within an output shaft functionally associated with said body portion.
 15. The torque generating device of claim 14, also including a replaceable piece removably and replaceably connectable to said torque generating device via said quadrilobe connector, said replaceable piece comprising a male quadrilobe connector portion protruding therefrom, said protrusion corresponding in shape to said quadrilobe socket of said female quadrilobe connector portion and configured to be received therein for connection of said replaceable piece to said body portion.
 16. The torque generating device of claim 10, wherein said torque generating device comprises one of a hydraulic torque wrench or a pneumatic torque wrench 